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Financial Instruments (Schedule Of Derivative Instruments) (Details) € in Millions, lb in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021 USD ($) lb	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) lb	Jun. 30, 2020 USD ($)	Sep. 30, 2019 EUR (€)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	$ 24	$ (35)	$ 64	$ (10)
Gain (loss) to other comprehensive income	15	(28)	44	(67)
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	13	(4)	24	(8)
Commodity Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	8	17	34	1
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount of foreign currency hedge positions	1,900		1,900
Foreign Exchange Contract [Member] \| Other deductions, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	8	(26)	33	(5)
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	3	(3)	5	8
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Cost of Sales [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	1	21	28	(28)
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified to earnings	0	(2)	2	(5)
Foreign Exchange Contract [Member] \| Cash Flow Hedging [Member] \| Sales [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	0	6	3	1
Foreign Exchange Contract [Member] \| Net Investment Hedging [Member] \| Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to other comprehensive income	6	$ (72)	(21)	$ (41)
All Commodity Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of commodities hedged	$ 139		$ 139
Copper and Aluminum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Weight in pounds of copper and aluminum commodity hedges \| lb	42		42
Senior Notes [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Debt, face amount \| €					€ 1,500